Among a cohort of more than 300 000 individuals being treated for moderate-to-severe asthma, more than 40% increased prescription refills for short-acting beta-2 agonists (SABA) in the 30 days before experiencing an exacerbation event, according to findings of a new study of administrative claims.
The researchers also found that during the same pre-exacerbation period, approximately 40% of individuals did not have anti-inflammatory maintenance medication on hand, leaving them at risk for increased exacerbation-related morbidity.
The findings were published in the Annals of Allergy, Asthma & Immunology.
Persons with moderate-to-severe asthma experience increased airway inflammation and related symptoms prior to a disease exacerbation, Miguel J Lanz, MD, physician-researcher in allergy and asthma at AAADRS Clinical Research Center, and colleagues wrote. The physiologic and clinical decline, they continue, typically happens "in the 10 days preceding an asthma exacerbation and may represent a 'window of opportunity,' where timely administration of anti-inflammatory therapy with fast-acting bronchodilators...could prevent an event from occurring."
For a more focused picture of medication use, Lanz and the research team evaluated the patterns of as-needed SABA and maintenance therapy treatment claims in patients with moderate-to-severe asthma before and after a severe exacerbation serious enough to result in a face-to-face clinical encounter; they compared findings between children aged 4 to 11 years and adults or adolescents aged ≥12 years.
The research team collected participant data from Merative MarketScan research databases for claims made between 2011 and 2017. Investigators identified 319 342 individuals with diagnostic codes for moderate-to-severe asthma; the group was comprised of 95 887 children aged 4 to 11 years (mean age, 7.2 years) and 223 455 adolescents and adults aged 12 years and older (mean age, 41.6 years). Slightly more than half the cohort were women (54%).
Investigators identified 164 485 patients (51.5%) with one or more severe exacerbations and 63 561 (19.9%) with one or more serious exacerbations.
A greater proportion of children than of adolescents or adults experienced both serious and severe exacerbations (P < .05 for both). Compared with the latter 2 groups, children had 22% greater odds of a severe asthma exacerbation (95% CI, 1.2-1.24) and 85% greater odds of a serious exacerbation event (95% CI, 1.81-1.88).
Analysis of pre- and post-exacerbation medication patterns found that the cumulative proportions of patients who filled prescriptions for a SABA and for a maintenance medication increased as an exacerbation event got closer, according to the study.
The researchers reported that within 30 days prior to the serious exacerbation, the cumulative proportion of patients with one or more SABA fills was 42.6%; the corresponding proportion for a maintenance medication fill was 57.4%, which meant 42.6% of patients did not claim a maintenance medication in the 30 days before an exacerbation.
Overall, 52.1% of these patients with a SABA fill filed those claims during the 10 days before the event. Among those who filled a SABA claim within 30 days post-event, most did so within the first 10 days afterward.
In the month before an exacerbation event, Ganz et al found that children had greater odds of having one or more SABA medication fills (44.3% vs 41.5%; OR = 1.12; 95% CI, 1.09-1.16) and of having one or more maintenance medication fills (59% vs. 56.3%; OR = 1.12; 95% CI, 1.08-1.15) compared with adolescents or adults.
During the 30 days that followed exacerbations, 61.4% of patients overall filled a SABA, including 69.7% of children and 55.6% of adults (OR = 1.84; 95% CI, 1.78-1.9). Similarly, 94.8% overall filled for a maintenance therapy, with children more likely to do so (98.6%) vs adolescents and adults (92.2%) (OR = 6.09; 95% CI, 5.45-6.81).
The researchers reported that all age groups appeared more likely to fill a SABA claim between 1 and 10 days after an event compared with between 1 and 10 days before an event (full cohort: OR = 5.89; 95% CI, 5.68-6.12; children: OR = 8.04; 95% CI, 7.57-8.54; adolescents and adults: OR = 4.73; 95% CI, 4.5-4.96).
In a similar vein, more than half (53.5%) of patients with a maintenance therapy claim made that fill in the 10-day period before the serious exacerbation compared with 97.3% in the 10-day period afterward (OR = 31.59; 95% CI, 29.94-33.33). The patterns were similar, according to the findings, for children (OR = 102.17; 95% CI, 89.03-117.24) and the adolescent and adult (OR = 20.68; 95% CI, 19.48-21.96) groups.
In terms of having a maintenance fill in the 10 days after versus the 30 days before an exacerbation event, the team calculated the odds were 9.0-fold higher in the overall population (95% CI, 8.67−9.25; P < .001), 31-fold higher in children aged 4 to 11 years (95% CI, 28.36−33.71; P < .001), and approximately 6-fold higher in adolescents or adults (95% CI, 5.72−6.16; P < .001).
Despite these increases in maintenance fills after exacerbation events, the researchers wrote, 30.6% of the cohort had multiple exacerbations during the post-index period.
Lanz et al point out that reliance on SABA medication is common among patients with asthma and that as sensitivity to triggers increases in the time leading to an exacerbation, the instinct is to reach for the rescue medication, a tendency borne out by the study findings that SABA refills increased leading up to an event. It is this period of increased SABA use that represents the window of opportunity to also increase use of inhaled corticosteroids, they emphasize, the combination being likely to prevent the exacerbation event. Approximately 40% of the patients apparently using more SABA, however, did not have a fill for maintenance anti-inflammatory medication.
"Although current treatment paradigms in the United States are predominantly based on the daily use of anti-inflammatory maintenance medication in combination with rescue SABA," the researchers concluded, "real-world claims patterns identified in this study indicate that this treatment paradigm does not sufficiently treat the increase in inflammation preceding an exacerbation."